Orange peel appearance on the flexed side of the extremities: many small punctate dimples in the skin of the flexed side of the extremities, resembling orange peel. The condition is caused by elastic pseudoxanthomatosis. Pseudoxanthoma elasticum used to be called diffuse xanthomas in the early days, and later it was called atypical xanthomas and dystrophic elastosis. Due to different inheritance modes, it can be divided into two types: autosomal dominant and autosomal recessive, and each type is divided into two groups. Clinically, it is common to see chromosome dominant group I and II and autosomal recessive group I, while autosomal recessive group II is more rare, and usually the symptoms of dominant inheritance are more serious than those of recessive inheritance. What causes elastosis pseudoxanthoma? The disease is a systemic elastic fiber disorder and the cause is unknown to date. Most people believe that it is related to congenital factors. There are the following views: 1. Family genetic theory. According to the fact that there is a family history of this disease, thus it is believed that this disease is related to heredity. 2, endocrine disorders. Thyroid or thymus hypertrophy, ovarian dysfunction, can cause this disease, thus inferring that this disease may be related to endocrine disorders. 3, metabolic disorders. Some people have skin histological examination of this disease found that there are elastic fiber formation and metabolic abnormalities. Some people also found that the lesions of the skin collagen content and pre-collagen proline hydroxylase activity is reduced. The disease is prevalent in young women and is characterized by skin damage, cardiovascular damage, gastrointestinal lesions, ocular lesions, neuropsychiatric lesions, and renal lesions. Skin damage usually occurs in adolescence, but can also be seen shortly after birth, the rash is symmetrical, occurring on both sides of the neck, umbilicus, armpits, popliteal fossa and inguinal folds, can also be seen in the oral cavity, the nasal mucosa, and occasionally can be seen in the vagina or the rectal mucosa, the skin is thickened, poorly elastic, flaccid, the skin rash is a pinhead size to pea-sized, for the yellowish to orange papules or small nodules, more clusters or fusion of the distribution of the network, part of the pores are enlarged, such as “”,” the skin is not very big. Part of the pores are enlarged, such as “plucked chicken skin”, the appearance of orange peel, there are also reports of calcification of the epidermis or penetrating skin degeneration, some patients may have skin hyperextension, but not necessarily with a rash. Cardiovascular damage includes peripheral vascular disease, hypertension, coronary artery disease and endocardial fibrosis and calcification, when the arteries of the limbs are involved, there may be a weakening or loss of pulse, intermittent claudication, angina attacks in about 1/3 of the cases, but the occurrence of acute myocardial infarction and sudden death is relatively rare, congestive heart failure may be associated with a variety of factors, vascular lesions and endocardial fibrosis can cause heart failure, hypertension and coronary artery disease is also an Hypertension and coronary artery disease are also important factors contributing to heart failure.